Technical Field
The embodiments herein generally relate to medical devices, and more particularly to foam cushion covers.
Description of the Related Art
The proper positioning of an immobile patient in a health care setting is a very important task. Patients must be positioned at the proper angle of turn and any device used to assist with supporting the patient must stay in place for the duration of time prescribed by the clinical staff. One device used to support patients in the elevated side lying position is a polyurethane foam wedge cushion. Foam wedges are available in a wide variety of dimensions, densities, and colors. Foam wedges are also available in bare foam or with a cover, which is intended to make the cushion easy to clean and reuse from one patient to another. Cover designs currently available offer some protection to the foam wedge inside the cover, but there are limits to how well the cushion can be sealed from contact with fluid and air contamination.
The most common method of joining the panels of the cover together is sewing. Sewing is fast and very cost effective, but the stitching creates small holes in the fabric and leaves very small gaps between the two pieces of fabric being joined. Fluid and air can pass through these very small spaces and inspections for permeation are difficult to do and are rarely done in the care environment. Another method of joining fabric panels together to form a cover is ultrasonic or radio frequency (RF) welding. This method uses a special adhesive and high frequency (HF) energy to join fabrics together and is the preferred approach because it does not leave small spaces like those found in sewn seams.
Whether a manufacturer chooses to use the sewing method or HF welding to join the seams of a foam cushion cover, the foam must maintain the ability to displace air. Polyurethane foam is an open celled structure that performs as a cushion by supporting with air and displacing air. Cushion covers sewn with seams permit the displacement of air through the small spaces in the seams. Both sewn and HF welded covers often use zipper enclosures, which permit airflow between the teeth of the zipper and through the spaces at either end of the zipper. If the cover is completely sewn or welded, a mesh or metal vent must be used to allow air to flow into and out of the cushion. Sewn seams, zipper enclosures, and vents all present the same potential for air and fluid borne pathogens to enter into the foam cushion. If the cushion becomes contaminated there is a high risk of spreading infection from one user to another within the healthcare environment. Accordingly, there is a need for a new type of foam cushion cover that reduces and/or eliminates the risk of cushion contamination and the spread of infectious pathogens.